1. Field of the Invention
The present invention relates to an image recording apparatus and an image recording method for recording an image by applying a coloring material on a recording medium in accordance with image data, and more particularly to an image recording apparatus and an image recording method which permit recording on both sides of the recording medium.
2. Related Background Art
With widespread use of a copier, an information processing apparatus such as a word processor or computer and a communication apparatus, an inkjet recording apparatus for recording a digital image by an inkjet method has rapidly come into wide use as one of output apparatuses for image forming (recording) of the above apparatuses. In the recording apparatus of this type, in order to improve a recording speed, a recording head which has integrated ink discharge ports and liquid paths is used as a recording head which has a plurality of ink discharge nozzles arranged integratedly, and recently, with the progress of color supporting, many of the apparatuses have been equipped with more than one recording head as above described together.
In an inkjet recording method, the recording is executed by applying ink as recording liquid, in the form of a spattering (or flying) droplet applied to a recording medium such as paper, and the method makes little noise because it is a non-contact method. Further, high concentration of the ink discharge nozzles can cause realization of high resolution and high speed recording, and moreover, no particular processing such as developing or fixing is required to be effected on a recording medium such as plain paper, and an image of high quality can be obtained at low cost, so that a range of uses of the method has been increased in recent years. Especially, an inkjet recording apparatus of an on-demand type is considered to have a potential for future demand since the apparatus is easily made to be color supporting and can be also miniaturized and simplified in itself. The variety of uses by users has also increased, which has accompanied various types of apparatuses coming into practical use. As an example, there is a recording apparatus including a both-side recording mechanism which permits recording on both sides of a recording medium.
In the recording apparatus including such a both-side recording mechanism, generally, ink is first applied on a surface (first recording side) of the recording medium to carry out recording on the surface, and then the recording medium is reversed to carry out recording on a reverse side (second recording side). At this time, if recording is carried out on a recording medium with relatively poor permeability of ink, the ink is not immediately permeated and it sometimes takes much time for the ink on the medium surface to be sufficiently dried (or fixed). When carrying out recording on the recording medium with such relatively poor fixing of the ink, it is necessary to set time between recording on the surface and recording on the reverse side relatively long. It is because, if the recording medium is to be reversed to start recording on the reverse side immediately after recording on the surface, the ink on the surface which is not sufficiently dried (or fixed) is made contact with a conveying path due to the above described reversing, and the ink on the surface and the conveying path are rubbed against each other to cause an ink stain. Accordingly, it is preferable to set a length of time between an end of surface recording and a start of reverse side recording such that the ink on the medium surface is sufficiently dried to cause no ink stain even if the recording medium is reversed. For example, in Japanese Patent Laid-Open No. 6-134982, a length of time between an end of surface recording and a start of reverse side recording is determined in accordance with a kind of a recording medium. According to the Japanese Patent Laid-Open No. 6-134982, a length of time is set relatively short in case of recording on a recording medium which ink permeates relatively quickly and on which the ink is well fixed, while the length of time is set relatively long in case of recording on a recording medium which the ink permeates relatively slowly and on which the ink is poorly fixed, thereby preventing an ink stain.
However, in the Japanese Patent Laid-Open No. 6-134982, the length of time between the end of surface recording and the start of reverse side recording is set in consideration of only the kind of the recording medium, so that the lengths of time are identically set even in case of recording on the same recording media in different printing duties. That is, the same length of time is required in either case of a high printing duty or a low printing duty. The inventor has found that, though acceptable in the case of the high printing duty, a time longer than needed is set in the case of the low printing duty, which causes a waste of time. That is, in the case of the low printing duty, the ink is fixed more quickly than in the case of the high printing duty, so that occurrence of an ink stain can be sufficiently restrained even if the time is set short.
As described above, conventionally, reduction of printing time in the case of the low duty has not been sufficiently achieved due to identically setting the time between the end of surface recording and the start of reverse side recording regardless of the printing duty. Under the present circumstances where high speed and high quality are required more and more, it is desirable to eliminate a waste of time to achieve reduction of printing time and to sufficiently restrain occurrence of an ink stain.